If you’re an avid scuba diver, you’re probably all too familiar with decompression sickness (DCS)—more commonly known as the bends—a disease that can strike astronauts, divers, and others, and arises after inadequately recompressing after changes in pressure gradients. In the marine environment, scientists long thought that many diving vertebrates—like sea turtles and marine mammals—were immune to DCS through various adaptations.
Editor’s Note: This is the last ocean roundup blog to be published before the Thanksgiving holiday, but be sure to check back on Monday, December 1 for more updates. Happy Thanksgiving!
- New 3D mapping around Antarctica found that sea ice surrounding Antarctica is thicker than thought. The scientists say it’s an important breakthrough to understanding how sea ice thickness and extent is changing. The Guardian
Australia is famous for its teeming, colorful biodiversity like sea turtles, giant clams, and coral, but it’s the Great Barrier Reef that often receives the most attention for its wildlife. Of course, other areas around Australia boast an incredible amount of unique wildlife, like the Ningaloo Marine Park along Australia’s West Coast, for example, that hosts whale sharks each March and April as they come to feed.
Last week, Oceana in Chile recommended that the Chilean government lower the total annual catch quota for common hake—a severely overexploited species— in 2015 by about 1,000 tons because of declines. According to Chile’s Fisheries Development Institute, common hake biomass declined by over six percent this year.
- A new study has unlocked a key to dolphin communication: The Indo-Pacific bottlenose dolphin and the common bottlenose dolphin use whistle sounds as names for each other, even in the wild. The researchers say this is an important step to understanding how human activity may be affecting these species. Phys.org
Every day, commercial and artisanal fishermen set out across the world’s oceans in search of their daily catch. Using harpoons, line-and-hooks, trawl nets, gill nets, and many, many more types of fishing gear, they set out to comb the oceans from the coast to the high seas in search of crab, tuna, swordfish, shrimp, and many more species. Of course, such high fishing pressure takes a toll on the oceans—leaving many fish stocks overfished, and critical habitat like coral reefs and seagrass beds in poor condition.
- New research shows that seals are picking up on the pings from acoustic tags on fish. Through experiments, the researchers found that seals located fish with acoustic tags on them more easily than untagged fish. BBC News
Ocean sunfish, also called the common mola, are arguably one of the ocean’s funniest looking fish. Their back fin that they are born with never actually grows, and instead just folds into itself and forms a blunt, flattened structure called the clavus, says National Geographic. This means that sunfish must swim by flapping their dorsal and anal fins side to side, making them sometimes appear to be awkward swimmers.
- In a high-tech experiment off of South Africa, researchers have started testing an electronic cable attached to the seafloor as a shark repellent. Because of sharks’ acute sense of electroreception, the researchers expect sharks to be able to detect the low-frequency field emitted from the cable. Reuters
Each year, thousands of people embark on whale watching tours in hope of spotting the majestic humpback whale in the wild. These baleen whales—who engage in lively leaps and flips, enhanced by their thin flippers and blue-back coloration—can put on quite the show for onlookers, but there is something extra special about encountering these marine mammals when it’s unexpected.